Author: Scott Bredemann
Updated: 03/25/2025 | Read Time: 4mins
When most people think of metals and electrical conductivity they immediately think of copper – but, what about aluminum? As a lightweight and widely available metal, aluminum is used in many industrial and electrical applications—but is it a good conductor of electricity?
The short answer is yes, aluminum does conduct electricity, but not as efficiently as copper. However, its lower cost and lighter weight make it a popular alternative in certain applications, such as power transmission lines and automotive wiring. In this article, we’ll explore how aluminum conducts electricity, how it compares to copper, and where it’s most commonly used.
Is Aluminum a Good Conductor of Electricity?
Aluminum does conduct electricity, but not as well as copper. Like all metals, aluminum allows electricity to flow because it has free electrons that move easily. However, it has a higher electrical resistance than copper, meaning it’s not quite as efficient at carrying current.
To put it in perspective, aluminum has about 61% of the conductivity of copper. That means an aluminum wire needs to be thicker than a copper wire to carry the same amount of electricity. Even so, aluminum is widely used in electrical applications because it’s lighter, more affordable, and naturally resistant to corrosion.
Below is a comparison of different metals based on their electrical conductivity, using copper as the reference (100% IACS, International Annealed Copper Standard):
| Metal | Electrical Conductivity (% IACS) | Resistivity (Ω·m × 10⁸) |
| Copper | 100% | 1.68 |
| Gold | 70% | 2.44 |
| Aluminum | 61% | 2.82 |
| Brass | 28%–37% | 6.98–4.87 |
| Nickel | 22% | 7.14 |
| Iron | 17% | 9.71 |
| Tin | 15% | 11.5 |
| Lead | 7% | 22 |
| Titanium | 3% | 42 |
Advantages and Disadvantages of Using Aluminum For Conductivity
Advantages:
- Lightweight – About one-third the weight of copper, making it ideal for power lines, aerospace, and other weight-sensitive applications.
- Cost-Effective – More affordable than copper, making it a budget-friendly option for large-scale electrical projects.
- Corrosion-Resistant – Forms a natural oxide layer that protects against rust and environmental damage.
- Good Conductivity – While not as conductive as copper, it still effectively carries electrical current when sized appropriately.
Disadvantages:
- Lower Conductivity Than Copper – About 61% as conductive as copper, meaning thicker wires are needed to achieve the same performance.
- Oxidation Issues – Forms an oxide layer that increases electrical resistance, which can lead to poor connections or overheating.
- Expands and Contracts More Than Copper – More susceptible to loosening in electrical connections over time due to thermal expansion.
- Requires Special Connectors – Needs coatings, anti-oxidation compounds, or specific connectors to ensure safe and reliable performance.
Common Applications of Aluminum in Electrical Conductivity
Aluminum is widely used in power transmission lines because of its lightweight and cost-effectiveness. High-voltage power lines need to span long distances, and using copper would make them significantly heavier and more expensive. To enhance strength, aluminum conductors are often reinforced with a steel core, creating what’s known as aluminum conductor steel-reinforced (ACSR) cables—a common sight in utility infrastructure.
Another major use is in automotive and aerospace wiring – aluminum wiring helps achieve this goal, especially in EV’s, where lighter materials contribute to extended battery range. It’s also used in aircraft wiring for the same reason—keeping weight to a minimum without compromising functionality.
In consumer electronics, aluminum is often found in heat sinks, which help dissipate heat in computers, LED lights, and other high-performance devices. While not used as frequently as copper in small-scale electrical circuits, aluminum’s affordability and thermal properties make it a solid choice in many applications.
Conclusion
If you have questions about the electrical conductivity needs within your projects or equipment, please feel free to contact our engineers, and product experts. Also, be sure to check out our catalog here at MISUMI USA, where we carry large array of aluminum offerings, including custom aluminum extrusion components.